Double acting pump



June 4, 1963 J. c. CRANFILL 3,092,033

DOUBLE ACTING PUMP Filed Aug. 26, 1960 2 Sheets-Sheet 1 FlG.l

FIG. IA

INVENTOR JOHN C. CRANFILL ATTORNEY June 4, 1963 J. c. CRANFILL DOUBLE ACTING PUMP 2 Sheets-Sheet 2 Filed Aug. 26. 1.960

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ATTORNEY FIG. 2

3,13%,033 DOUBLE ACTING PUMP John C. Cranfill, Odessa, Ector County, Tex. Filed Aug. 26, 1950, Ser. No. 52,207 6 Claims. (Cl. 103158) This invention relates to pumps, and more particularly to double-acting pumps adapted for operation in an oil well tubing string or any other tubular member.

Although my invention is described herein with reference to the tubing string of an oil well, it is to be emphasized that such wells are used for illustrative purposes only and that my invention is in no way limited to such use.

Eventually, if not at the outset, the bottom hole pressure of each oil well diminishes to the level where it is necessary to employ artificial means to raise the oil to the well head. Pumping is one of such means, although rather expensive. Such being the case, any improvement in the pumps used therefor, which will improve the efliciency of the pumps and, hence, lower the unit cost of such pumping, are welcomed by the industry.

One of the principally recognized ways of increasing this efiiciency in down-the-hole insert-type pumps is a means of effecting a producing stroke in addition to the upstroke, the upstroke usually being the one during which energy is applied at the wellhead. If any appreciable pumping action at all can be effected during the down stroke of such a pump, the device therefor will be considered a major advance in the art.

Accordingly, a principal object of my invention is to provide means for improving the efficiency of insert-type pumps.

Another object is to provide such means which, during the downstroke of the pump, employ the force of gravity without the requirement for additional energy from the well head.

Another object is to provide such means which employ the force of gravity acting on the sucker rods of the oil well to effect such efficiency.

Still another object is to provide such means which will effect pumping action on the downstroke as well as on the upstroke.

A further object is to provide improved means for existing insert-type pumps to be used down-the-hole to effect the foregoing objects.

Additional objects will be apparent from a study of the following disclosure and attached claims in conjunction with the drawings, wherein:

FIGURE 1 is an elevational view, partially in section, of my invention, an improved double-acting pump.

FIGURE l-A is an elevational view of the pump shown in FIGURE 1, as it would appear at the maximum point reached during the upstroke.

FIGURE 2 is an elevational view, partially in section, of a two-way valve comprising a portion of the pump shown in FIGURE 1.

FIGURE 2A is a sectional view taken on the line 2A2A of FIGURE 2.

FIGURE 23 is a partial view in elevation of FIG- URE 2.

FIGURE 3 is an elevational view, partially in section, of a traveling discharge valve, comprising still another portion of the pump shown in FIGURE 1.

Referring to FIGURES 1 and 1A, this disclosure of my invention will be commenced by describing the means and mode of operation of a simple, conventional downthe-hole pump without my improvement features.

In this description of the conventional pump the portions of my invention designated X and Y are disregarded, leaving for consideration at this time the portions desigenemas Patented June 4, 1953 ice nated W and Z. The conventional pump is comprised of a movable portion W and a fixed portion Z, which latter portion is secured and packed ofi in a tubing string (not shown) in the conventional manner by hold-down body 36 and sealing cups 37. Connected to hold-down body 36 by adapter 35 is a precision ground tube 27 which extends upwardly into movable portion W and has disposed at its upper end, and secured thereto, a conventional check valve 29. Although hold-down body 36 itself may be secured to the tubing string (not shown) of an oil well, connector 38 may be connected at its lower end to any of numerous types of packing devices to anchor portion Z in the tubing string. It will be noted that portion Z and all of its components are tubular, providing a passage way K upwardly through pull tube 27 to check valve 29. In this description plunger cage 3%, in which the check valve 29 is disposed, having a plurality of ports Site, is shown connected to plunger assembly 16. In the conventional pump plunger cage 30 would be connected to the upper end of pull tube 27.

Movable portion W of this conventional pump is movable in the vertical plane relative to fixed portion Z. Again the reader is requested to omit in his consideration of this conventional pump the portions X and Y, and to assume that pump tube 28 and liner jacket 25- are continuous (i.e., one continuous member) from the connection of pump tube 28 with tube bushing 31 downwardly to the connection of liner jacket 25 with adapter 34. Disposed within jacket 25, to act as a seal between jacket 25 and tube 27, and vertically between adapter 34 and an adapter such as adapter 24, is a liner section 26. Connected to the upper end of pump tube 28 to join the tube to cage 32 is a bushing 31. Bushing 31 also serves to secure seat 33 in order to dispose ball 33a within cage 32. Bushing 31 is tubular, and cage 32 contains a bore 32c in which ball 33a is disposed. Cage 32 contains a plurality of openings 32a for communicating bore 32c with the space thereabove. Cage 32 is also threaded at 32b for connecting sucker rods to the P p- In operation this conventional down-the hole pump is lowered into the tubing string (not shown) and is secured therein at the oil level within the well by fixed portion Z, or other means, as described hereinbefore. Now, the pump is operated simply by pulling upwardly by a force exerted on the sucker rods at the wellhead, which moves movable portion W of the pump to the position, with respect to fixed portion Z, shown in FIG- URE 1A. When this occurs ball 29a is raised, or lifted, from its seat 29, and the space G between the upper end of cage 30 and the lower end of bushing 3:1 is enlarged. During this time ball 33a is forced downwardly by any liquids thereabove and remains seated on seat 33. After this pumping action has been continued for a period of time, by repeated strokes, tube 27 is filled with liquid; and on the next upstroke of the pump, when space G enlarges, ball 29:: is lifted from its seat and the liquid flows through ports 30a into space G. Now, on the downstroke ball 2% is forced back on its seat, preventing the escape of liquid from space G back into tube 27. During this time the liquid in space G forces ball 33a from its seat, and the liquid in space G passes upwardly through ports 3211 into the tubing above the pump. Repeated strokes of the pump eventually force the successive increments of fluid pumped into space G and bore 32c upwardly through the tubing and out the tubing at the wellhead.

It will be noted that in this conventional pump fluid is forced outwardly through ports 32a only during the downstroke of movable portion W, and that it is lifted upwardly in the tubing string (not shown) only during the upstroke of the portion W, when ball 33a is forced downwardly on seat 33.

This basic stroke of the pump is maintained in my invention; however, in my invention pumping or lifting action is effected during the downstroke of the pump as well as during the upstroke, all as described under the headings Construction and Operation and claimed, hereinafter.

Construction Using as a reference the conventional pump as described hereinbefore, it will be noted that poition X, shown and described as a two-way valve in FIGURE 2, is connected to the upper end of tube 27, and by means of section 16 is connected to the lower end of cage 3t Also, it will be noted that portion Y, discharge valve, FIGURE 3, is disposed about tube 27 between jacket 25 and tube 27. Of course, in this configuration portion Y (FIGURE 3) moves with portion W, and portion X (FIGURE 2) remains stationary with portion Z.

Referring now to FIGURE 2, two way valve constituting a part of my invention, is seen to be comprised of lower section 12 connected threadedly to tube 27 and tubular member 18 threadedly connected to lower section 12 at its lower end and to cage 19 at its upper end, the upper end of cage 19 being threadedly connected to the lower end of plunger 16, the upper end of which is connected, as described hereinbefore, to the lower end of cage 39. Each of these members, except as stated otherwise hereinafter, is tubular. Secured between lower section 12 and reduced-diameter portion 18a of upper section 13 is seat 13 on which rests ball 13a. Of course, ball 13a serves to prevent communication between bore K and passageway B which leads to the exterior of section 18. Seat 15 is disposed within cage 19 and is secured therein between the upper end of section 18 and flange 19a of cage 19. Ball 15a rests on seat 15 to prevent communication between spaces E and F, unless raised from its seat. It will be noted that lower section ll contains a plurality of ports H which serve to permit communication between bore K and space C, which latter space is formed between lower section 12 and cage 18. Sectional view 2A taken along line 2A2A (FIG. 2) shows two (2) passageways D which serve to permit communication between space C and space E above solid portion 8a, the purpose of which will be set forth more fully under Operation hereinbelow.

Traveling discharge valve Y shown in detail in FIGURE 3, is comprised of adapter 24 threadedly connected at its upper end to body 22; cover guide 23 disposed exteriorly of body 22 and between adapter 24 and flanged portion 22:! to form space N; valve 20 disposed about the elongated pontion of body 22 and below flange portion 22a of body 22; and spring 21 disposed within space N and biasing valve 20 upwardly into contact with flange portion 22a in such manner as to seal passageways P which pass through flange portion 22a. The lower end of adapter 24 is threadedly connected to jacket 25, and its lower end abuts the upper end of liner 26 which, as described hereinbefore, serves to seal tube 27. The upper end of body 22 is threadedly connected to the lower end of tube 28. Spring 21 acts against the upper end of adapter 24 and the lower end or surface of valve 26 in such manner as to force valve 20 upwardly against the lower surface of flange 22a. The interface 20a of body 20 and flange 22a is machined to such a degree that when valve 20 is biased upwardly, passageway P is closed. Cover guard 23 contains a plurality of circumferentially spaced ports M permitting communication between space N and the exterior of discharge valve Y. Except for valve 20, communication may be had between spaces A and N through passageways P.

Referring to FIGS. 1 and 2 it will be noted that tube 28 (FIG. 1) is not shown disposed about the exterior of twoway valve X shown in FIG. 2. In this connection, it should be pointed out that any fluid passing outwardly through ports B can communicate downwardly to space A, it not being intended that the interface between discharge valve X and tube 28 be sealed. In fact, it is intended that such interface not exist, so that communication may be had between :ports B and space A. Furthermore, it is to be noted that since two-way valve X is immovable and traveling discharge valve Y is movable with respect thereto, space A is subject to, and actually does, decrease from the volume shown in FIGURE 1 to an insignificant volume, determined by the upper end of body 22 contacting the lower end of section 12 at the upper limit of the upstroke of the pump.

Operation In this description of the operation of my invention it is assumed: First, portion Z (FIGURE 1) is secured in a tubing string (not shown) and sealing cups 37 seal the interface of portion Z and the interior of the tubing string; secondly, the pump (FIGURE 1) is in the configuration shown in FIGURE 1; thirdly, the tubing string from the producing zone upwardly through the pump and to the wellhead is filled with liquid; and, fourthly, all spaces and passageway-s of the pump are filled with liquid.

During the upstroke of movable portion W and traveling discharge valve Y the following events and relationships take place: First, ball 33a is seated and forced down upon seat 33, ball 29a is raised from seat 29, space G increases in volume, and the liquid in space F passes upwardly past ball 29a into space G; secondly, due to the loss of fluid from space F a partial vacuum is created therein lifting ball 15a off of seat 15, permitting fluid to f flow upwardly past ball 15a from passageway K, through ports H, into passageway C, through passageways D into:

space E; thirdly, the upper end of body 22 moves upwardly toward the lower end of section 12, decreasing space A, which exerts a force on ball through ports B causing ball 13a to seat on seat 13, exerting a force through passageways P on valve 20 and spring 21 causing valve 20 to unseat, and fluid to pass downwardly through passageways into space N and outwardly through ports M into the tubing exteriorly thereof; and, lastly, the volume between the lower end of adapter 34 and the upper end of adapter 35 increases.

The net result of these changes in position of the various components is that, first, the increase of volume within the tubing string between adapters 34 and 35 is offset by the elevation of top cage 32 in the tubing string, and, secondly, the liquid from space A expelled outwardly into the tubing string through ports M is forced upwardly, displacing fluid from the tubing string outwardly through the wellhead.

During the downstroke of the pump and sucker rods, the following events and relationships transpire: First, the volume occupied within the tubing string 'by cage 32 is decreased and the space between adapters 34 and 35 is decreased correspondingly; secondly, ball 29a is seated on and compressed against seat 29, ball 33a is forced from its seat by the fluid in space G, and the fluid from space G is forced upwardly past ball 33a, into space 32c, and through ports 32a into the tubing string; thirdly, ball 15a is forced against and seated on seat 15 trapping the fluid between ball 15a and ball 29a in space F; fourthly, space A increases to the volume shown in FIGURE 1, due to the fact that the upper end of body 22 moves downwardly with respect to the lower end of section 12, a partial vacuum being created in space A, and spring 21 forces valve 20 upwardly against the lower surface of flange 22a; and, lastly, fluid from within space K passes upwardly past ball 13a, raised from its seat due to the partial vacuum created in space A, through ports B and downwardly into space A. The net result of these events is that the liquid forced outwardly from space G past ball 33a and through ports 32a displaces liquid thereabove which is forced outwardly through the wellhead.

Of course, during the upstroke the force necessary to effect a pumping action is supplied at the wellhead and moves downwardly through the tubing string to the top of the pump 32b by means of sucker rods, or the like. As seen heretofore, liquid is raised to the wellhead and therefrom during the upstroke of the pump. During the downstroke pumping action is had, and a good part of the energy required therefor is furnished by gravity acting on the mass of the sucker rods and the movable portion W of the pump.

From the foregoing it is seen that pumping action is had during the upstroke and during the downstroke of my invention. 1

It is further seen that the force of gravity is utilized to produce pumping action during the downstroke of my improved pump. It is also seen that during the upstroke and the downstroke of my improved double-acting pump liquid is produced from therebelow.

It is to be understood that the form of the invention shown and described is to be taken as a preferred embodiment of the same, and that various changes in the shape, size, and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the attached claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

l. A double acting pump for use in a well casing, comprising: adapter means releasably secur-able in said casing; tube means partially enclosing and reciprocable relative to said adapter means, said adapter means having an interface with said casing, having check-valve means at its upper end, and being secured in and packing off said interface with said casing at a point adjacent its opposite end; first valve means made up in said adapter means below said check-valve means for diverting fluid flow from said adapter means alternately into said casing above said adapter means through the upper portion of said tube means during downward reciprocation of said tube means relative to said adapter means and into said tube means during reciprocation of said tube means in said downward direction; said first valve means having a first closeable passage for diverting fluid flow into the lower pontion of said tube means and a second ClOSCElJblG passage for diverting fluid flow into the upper portion of said tube means; and second valve means forming a part of the lower portion of said tube means for discharging fluid from said tube means into said casing below the upper end of said adapter means upon upward reciprocation of said tube means, said second valve means having a closeable passage permitting fluid flow from said first passage into said casing.

'2. A double acting pump for use in a well casing comprising: adapter means for securing and packing off said pump in said casing and having two-way valve means comprising a portion of its length; tube means enclosing said two-way valve means, reciprocably moveable relative to said adapter means, and slidably enclosing an upper portion of said adapter means; said two-way valve means having a first closeable passage for diventing fluid flow into the lower portion of said tube means and a second closeable passage for diverting fluid flow into the upper portion of said tube means; said tube means having an upper passage permitting the flow of fluid into said casing above said tube means and a lower closeable passage permitting fluid fiow from said first passage into said casing, whereby fluid is moved through said pump to a point thereabove upon reciprocation of said tube means relative to said adapter means.

3. A double acting pump for use in a well casing comprising: adapter means securing and packing off said pump in said casing; tube means enclosing a part of and reciprocably moveable relative to said adapter means; two-way valve means secured to said adapter means and enclosed within said tube means; and discharge-valve means comprising a part of said tube means and slidably enclosing a part of said adapter means below said twoway valve means; said two-way valve means having a first 6 closeable passage for diverting fluid flow into said dis charge-valve means and a second closeable passage for diverting fluid flow into the upepr portion of said tube means; said tube means having a passage through its upper end permitting the flow of fluid into said casing above said tube means upon downward reciprocation of said tube means, said discharge-valve means permitting fluid flow from said first passage into said casing upon upward reciprocation of said tube means, whereby fluid is moved from below said pump into the casing thereabove.

4. A double acting pump for use in a well casing comprising: tubular adapter means, securing said pump in said casing, having a tube extending therefrom and a tube check valve connected to the opposite end of said tube; a two-way valve, made up in said tube below said tube check valve, having diversion means for permitting flow from said tube to pass exteriorly thereof and to a point below said tube check valve, a lower check valve made up in said two-way valve preventing flow from exteriorly thereof into said tube, and an upper check valve comprising the upper end of said two-way valve preventing flow from above said two-way valve into said tube therebelow; tube means sealingly disposed about the upper portion of said tube, reciprocably moveable relative to said tube, creating an upper chamber between the upper end of said tube and said tube means having variable capacity as said tube means is reoiprocated relative to said tube and having a production check valve above said tube check valve to prevent flow from above said pump into said upper chamber; and discharge valve means sealingly disposed about said tube below said two-way valve for regulating flow from said diversion means exteriorly of said tube means, said discharge valve means, said tube means, and said tube creating a lower chamber of variable capacity connecting said two-way valve means and said discharge valve means; said tubular adapter means, said two=way valve, the upper portion of said tube, said upper chamber, and the upper portion of said tube means defining a first passage, and said tubular adapter means, said two-way valve, said lower chamber, and said discharge valve means defining a second passage, whereby upon upward reciprocation of said tube means fluid is moved through said pump from below said tubular adapter means into said casing thereabove, and upon downward reciprocation of said tube means fluid is moved through said pump from below said tubular adapter means into said casing thereabove.

5. A double acting pump for use in a well casing comprising: tubular adapter means for securing said pump in said casing and packing off said well, having a tube extending upwardly therefrom, and a tube check valve connected to the upper end of said tube; two-way valve means, made up in said tube below said tube check valve forming a tube chamber in said tube below said tube check valve, having diversion means permitting flow from said tube to the exterior thereof and to said tube chamber, a lower check valve made up in said two-way valve preventing backflow from exteriorly of said tube, and an upper check valve comprising the upper end of said two-way valve above said lower check valve preventing back-flow from said tube chamber; tube means disposed about and enclosing the upper portion of said tube with a production check valve adjacent its upper end, movable relative to said tube, creating an upper chamber of variable capacity intermediate said production and said tube check valves above said tube, and having seal means disposed to form an outer annular chamber of variable capacity below said two-way valves; and discharge valve means made up in said tube means below said two-way valve and disposed in said outer annular chamber to permit flow from said outer annular chamber to the exterior of said tube means upon upward reciprocation of said tube means relative to said adapter means; said adapter means, said two-Way valve means said tube chamber, said upper chamber, and the upper end portion of said tube means defining a first passage, and said adapter means, said two-way valve means, said outer annular chamber, and said discharge valve means defining a second passage; fluid moving from below said pump through said first passage into said casing thereabove upon downward reciprocation of said tube means, and fluid moving from below said pump, through said second passage and into said casing thereabove upon upward reciprocation of said tube means.

6. A two-way valve for use in a conventional down-thehole Well pump comprising: first tubular means having 10 a port adjacent its upper end; a second tubular means enclosing part of and connected to said first tubular means to form an annular chamber exteriorly of said first tubular means, having a first passage communicating with the interior of said first tubular means, and having a second passage independent of said first passage, communicating the interior of its upper portion with said chamber; third References Cited in the file of this patent UNITED STATES PATENTS 1,063,699 Erb June 3, 1913 1,278,264 Weinman Sept. 10, 1918 2,300,121 Justis Oct. 27, 1942 2,807,218 Hanlen Sept. 24, 1957 

1. A DOUBLE ACTING PUMP FOR USE IN A WELL CASING, COMPRISING: ADAPTER MEANS RELEASABLY SECURABLE IN SAID CASING; TUBE MEANS PARTIALLY ENCLOSING AND RECIPROCABLE RELATIVE TO SAID ADAPTER MEANS, SAID ADAPTER MEANS HAVING AN INTERFACE WITH SAID CASING, HAVING CHECK-VALVE MEANS AT ITS UPPER END, AND BEING SECURED IN AND PACKING OFF SAID INTERFACE WITH SAID CASING AT A POINT ADJACENT ITS OPPOSITE END; FIRST VALVE MEANS MADE UP IN SAID ADAPTER MEANS BELOW SAID CHECK-VALVE MEANS FOR DIVERTING FLUID FLOW FROM SAID ADAPTER MEANS ALTERNATELY INTO SAID CASING ABOVE SAID ADAPTER MEANS THROUGH THE UPPER PORTION OF SAID TUBE MEANS DURING DOWNWARD RECIPROCATION OF SAID TUBE MEANS RELATIVE TO SAID ADAPTER MEANS AND INTO SAID TUBE MEANS DURING RECIPROCATION OF SAID TUBE MEANS IN SAID DOWNWARD DIRECTION; SAID FIRST VALVE MEANS HAVING A FIRST CLOSEABLE PASSAGE FOR DIVERTING FLUID FLOW INTO THE LOWER PORTION OF SAID TUBE MEANS AND A SECOND CLOSEABLE PASSSAGE FOR DIVERTING FLUID FLOW INTO THE UPPER PORTION OF SAID TUBE MEANS; AND SECOND VALVE MEANS FORMING A PART OF THE LOWER PORTION OF SAID TUBE MEANS FOR DISCHARGING FLUID FROM SAID TUBE MEANS INTO SAID CASING BELOW THE UPPER END OF SAID ADAPTER MEANS UPON UPWARD RECIPROCATION OF SAID TUBE MEANS, SAID SECOND VALVE MEANS HAVING A CLOSEABLE PASSAGE PERMITTING FLUID FLOW FROM SAID FIRST PASSAGE INTO SAID CASING. 